git:20260216.41d074f to git:20260324.a02e282

---

name: drawio-logical-diagrams

description: 'Creates professional logical flow diagrams and logical system architecture diagrams using draw.io XML format (.drawio files). Use when creating: (1) logical flow diagrams showing data/process flow between system components, (2) logical architecture diagrams representing system structure without cloud provider specifics, (3) BPMN process diagrams, (4) UML diagrams (class, sequence, activity), (5) data flow diagrams (DFD), (6) decision flowcharts, or (7) system interaction diagrams. This skill focuses on generic/abstract representations, not AWS/Azure-specific architectures (use aws-drawio-architecture-diagrams for cloud diagrams).'

allowed-tools: Read, Write, Bash

---

# Draw.io Logical Diagrams Creation

## Overview

## When to Use

- Creating logical flow diagrams showing data flow between system components

- Designing logical architecture diagrams (abstract system structure)

- Building BPMN process diagrams for business processes

- Drawing UML diagrams (class, sequence, activity, state)

- Creating data flow diagrams (DFD) for system analysis

- Making decision flowcharts with branching logic

- Visualizing system interactions and sequences

- Documenting logical system design without cloud specifics

## Instructions

### Creating a Logical Diagram

1. **Analyze the request**: Understand the system/process to diagram

2. **Choose diagram type**: Flowchart, architecture, BPMN, UML, DFD, etc.

3. **Identify elements**: Determine actors, processes, data stores, connectors

4. **Draft XML structure**: Create the mxGraphModel with proper root cells

5. **Add shapes**: Create mxCell elements with appropriate styles

6. **Add connectors**: Link elements with edge elements

8. **Output**: Write the .drawio file for the user

### Key XML Components

## Draw.io XML Structure

```xml

<mxfile host="app.diagrams.net" agent="Claude" version="24.7.17">

<diagram id="logical-flow-1" name="Logical Flow">

<mxGraphModel dx="1200" dy="800" grid="1" gridSize="10" guides="1"

tooltips="1" connect="1" arrows="1" fold="1" page="1"

pageScale="1" pageWidth="1169" pageHeight="827" math="0" shadow="0">

<root>

<mxCell id="0" />

<mxCell id="1" parent="0" />

<!-- Shapes and connectors here -->

</root>

</mxGraphModel>

</diagram>

</mxfile>

```

**Key rules:**

- IDs "0" and "1" are reserved for root cells

- Use sequential integer IDs starting from "2"

- Use landscape orientation for architecture diagrams

- All coordinates must be positive and aligned to grid (multiples of 10)

## Generic Shapes and Styles

### Basic Shape Types

| Shape | Style |

|-------|-------|

| Rectangle | `rounded=0;whiteSpace=wrap;html=1;` |

| Rounded Rectangle | `rounded=1;whiteSpace=wrap;html=1;` |

| Ellipse/Circle | `ellipse;whiteSpace=wrap;html=1;` |

| Diamond | `rhombus;whiteSpace=wrap;html=1;` |

| Cylinder | `shape=cylinder3;whiteSpace=wrap;html=1;boundedLbl=1;` |

| Hexagon | `shape=hexagon;perimeter=hexagonPerimeter2;whiteSpace=wrap;html=1;` |

| Parallelogram | `shape=ext;double=1;rounded=0;whiteSpace=wrap;html=1;` |

### Standard Color Palette

| Element Type | Fill Color | Border Color | Usage |

|--------------|------------|--------------|-------|

### Connector Styles

**Standard flow:**

```

edgeStyle=orthogonalEdgeStyle;rounded=0;orthogonalLoop=1;jettySize=auto;html=1;endArrow=classic;endFill=1;strokeColor=#666666;strokeWidth=2;

```

**Dashed (alternative/optional):**

```

edgeStyle=orthogonalEdgeStyle;dashed=1;dashPattern=5 5;strokeColor=#666666;

```

**Arrow head styles:**

- `endArrow=classic;endFill=1` - Filled triangle

- `endArrow=open;endFill=0` - Open arrow

- `endArrow=blockThin;endFill=1` - Block arrow

## Diagram Types

## Reference Files

- [diagram-templates.md](references/diagram-templates.md) - Ready-to-use templates

## Examples

```xml

<mxfile host="app.diagrams.net" agent="Claude" version="24.7.17">

<diagram id="order-flow-1" name="Order Processing">

<mxGraphModel dx="1200" dy="800" grid="1" gridSize="10" guides="1" tooltips="1" connect="1" arrows="1" fold="1" page="1" pageScale="1" pageWidth="1169" pageHeight="827" math="0" shadow="0">

<root>

</root>

</mxGraphModel>

</diagram>

</mxfile>

```

### Example 2: Three-Tier Logical Architecture

```xml

<mxfile host="app.diagrams.net" agent="Claude" version="24.7.17">

<diagram id="three-tier-1" name="Three-Tier Architecture">

<mxGraphModel dx="1200" dy="800" grid="1" gridSize="10" guides="1" tooltips="1" connect="1" arrows="1" fold="1" page="1" pageScale="1" pageWidth="1169" pageHeight="827" math="0" shadow="0">

<root>

</root>

</mxGraphModel>

</diagram>

</mxfile>

```

## Constraints and Warnings

### Critical Constraints

1. **XML validity**: Always close tags properly and escape special characters

2. **Unique IDs**: All cell IDs must be unique (except parent "0" and "1")

3. **Valid references**: Source/target must reference existing cell IDs

4. **Positive coordinates**: All x, y values must be >= 0

### Warnings

- XML files must be well-formed or will fail to open in draw.io

- Invalid parent references cause elements to disappear

- Negative coordinates place elements outside visible canvas

## Best Practices

2. Keep arrows straight with minimal bends

3. Place labels at least 20px from arrow lines

4. Group related elements in containers

5. Use 12-14px font for labels, 10-11px for annotations